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| author |   Ingo Molnar <mingo@elte.hu> | 2008-02-04 16:47:54 +0100 |
|---|---|---|
| committer | Ingo Molnar <mingo@elte.hu> | 2008-02-04 16:47:54 +0100 |
| commit | 38cb47ba0187c481aa949d3bbf149e014e8cacda (patch) | |
| tree | ff05de005f1838b8eefedcb03a8247b2c825b5b3 /arch/x86/mm | |
| parent | Merge git://git.kernel.org/pub/scm/linux/kernel/git/bart/ide-2.6 (diff) | |
| download | linux-dev-38cb47ba0187c481aa949d3bbf149e014e8cacda.tar.xz linux-dev-38cb47ba0187c481aa949d3bbf149e014e8cacda.zip | |
x86: relax RAM check in ioremap()
Kevin Winchester reported the loss of direct rendering, due to:
[ 0.588184] agpgart: Detected AGP bridge 0
[ 0.588184] agpgart: unable to get memory for graphics translation table.
[ 0.588184] agpgart: agp_backend_initialize() failed.
[ 0.588207] agpgart-amd64: probe of 0000:00:00.0 failed with error -12
and bisected it down to:
commit 266b9f8727976769e2ed2dad77ac9295f37e321e
Author: Thomas Gleixner <tglx@linutronix.de>
Date: Wed Jan 30 13:34:06 2008 +0100
x86: fix ioremap RAM check
this check was too strict and caused an ioremap() failure.
the problem is due to the somewhat unclean way of how the GART code
reserves a memory range for its aperture, and how it utilizes it
later on.
Allow RAM pages to be ioremap()-ed too, as long as they are reserved.
Bisected-by: Kevin Winchester <kjwinchester@gmail.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Tested-by: Kevin Winchester <kjwinchester@gmail.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Diffstat (limited to 'arch/x86/mm')
| -rw-r--r-- | arch/x86/mm/ioremap.c | 9 |
1 files changed, 5 insertions, 4 deletions
diff --git a/arch/x86/mm/ioremap.c b/arch/x86/mm/ioremap.c index c004d94608fd..1a88d1572a77 100644 --- a/arch/x86/mm/ioremap.c +++ b/arch/x86/mm/ioremap.c @@ -116,7 +116,7 @@ static void __iomem *__ioremap(unsigned long phys_addr, unsigned long size, { void __iomem *addr; struct vm_struct *area; - unsigned long offset, last_addr; + unsigned long pfn, offset, last_addr; pgprot_t prot; /* Don't allow wraparound or zero size */ @@ -133,9 +133,10 @@ static void __iomem *__ioremap(unsigned long phys_addr, unsigned long size, /* * Don't allow anybody to remap normal RAM that we're using.. */ - for (offset = phys_addr >> PAGE_SHIFT; offset < max_pfn_mapped && - (offset << PAGE_SHIFT) < last_addr; offset++) { - if (page_is_ram(offset)) + for (pfn = phys_addr >> PAGE_SHIFT; pfn < max_pfn_mapped && + (pfn << PAGE_SHIFT) < last_addr; pfn++) { + if (page_is_ram(pfn) && pfn_valid(pfn) && + !PageReserved(pfn_to_page(pfn))) return NULL; } |